Inspection apparatus and inspection method

Abstract

An inspection apparatus includes a light source unit, cameras, a keyboard, and a controller that determines a wavelength of the excitation light, based on the information on the emission color received by the keyboard, and that controls the light source unit so that the light source unit generates excitation light with the determined wavelength. The controller determines a wavelength longer than an absorption edge wavelength of the substrate of the sample and shorter than a peak wavelength of an emission spectrum of the light-emitting element, the peak wavelength being specified from the information on the emission color, to be the wavelength of the excitation light.

The invention claimed is: 
     
       1. An inspection apparatus inspecting an object comprising a substrate bearing a plurality of light-emitting elements, the inspection apparatus comprising:
 a light source detector configured to generate excitation light emitted on a light-emitting element; 
 a light detector configured to detect emitted light from the light-emitting element exposed to the excitation light; 
 an input unit configured to receive information on an emission color of the light-emitting element; and 
 a controller configured to determine a wavelength of the excitation light, based on the information on the emission color received by the input unit, the controller controlling the light source so that the light source generates the excitation light with the determined wavelength, wherein 
 the controller determines a wavelength longer than an absorption edge wavelength of the substrate of the object and shorter than a peak wavelength of an emission spectrum of the light-emitting element, the peak wavelength being specified from the information on the emission color, to be the wavelength of the excitation light. 
 
     
     
       2. The inspection apparatus according to  claim 1 , wherein
 the controller determines a wavelength shorter than a wavelength given by subtracting a full width half maximum of an emission spectrum of the light-emitting element from a peak wavelength of the emission spectrum of the light-emitting element, to be a wavelength of the excitation light. 
 
     
     
       3. The inspection apparatus according to  claim 1 , wherein
 the light source comprises a white light source of the excitation light and a plurality of first band-pass filters configured to transmit beams of the excitation light with different wavelength bands, and 
 the controller switches one of the first band-pass filters according to a determined wavelength of the excitation light. 
 
     
     
       4. The inspection apparatus according to  claim 1 , wherein
 the light source comprises a plurality of light sources configured to generate beams of the excitation light with different wavelengths, and 
 the controller switches the plurality of light sources according to a determined wavelength of the excitation light. 
 
     
     
       5. The inspection apparatus according to  claim 1 , further comprising
 a plurality of second band-pass filters configured to transmit beams of emitted light with different wavelength bands, wherein 
 the controller switches one of the second band-pass filters disposed in an optical path leading from the light-emitting element to the light detector, according to a determined wavelength of the excitation light. 
 
     
     
       6. The inspection apparatus according to  claim 1 , further comprising
 a plurality of first wavelength separation elements configured to define wavelengths different from each other as first separation wavelengths, respectively, and configured to separate the excitation light from the emitted light by using the first separation wavelength as separation reference, wherein 
 the controller switches one of the first wavelength separation elements disposed in an optical path leading from the light source to the light-emitting element and in an optical path leading from the light-emitting element to the light detector, according to a determined wavelength of the excitation light. 
 
     
     
       7. The inspection apparatus according to  claim 1 , further comprising
 a plurality of second wavelength separation elements configured to define wavelengths different from each other as second separation wavelengths, respectively, and configured to separate emitted light with a wavelength longer than the second separation wavelength from emitted light with a wavelength shorter than the second separation wavelength by using the second separation wavelength as separation reference, wherein 
 the light detector comprises: a first photodetector configured to, from among beams of the emitted light, detect emitted light with a wavelength longer than the second separation wavelength; and a second photodetector configured to, from among beams of the emitted light, detect emitted light with a wavelength shorter than the second separation wavelength, and 
 the controller switches one of the second wavelength separation elements disposed in an optical path leading from the light-emitting element to the first photodetector and the second photodetector, according to a determined wavelength of the excitation light. 
 
     
     
       8. The inspection apparatus according to  claim 1 , further comprising:
 a plurality of second band-pass filters configured to transmit beams of the emitted light with different wavelength bands; a plurality of first wavelength separation elements configured to define wavelengths different from each other as first separation wavelengths, respectively, and configured to separate the excitation light from the emitted light by using the first separation wavelength as separation reference; and a plurality of second wavelength separation elements configured to define wavelengths different from each other as second separation wavelengths, respectively, and configured to separate emitted light with a wavelength longer than the second separation wavelength from emitted light with a wavelength shorter than the second separation wavelength by using the second separation wavelength as separation reference, wherein 
 the light source comprises: a white light source of the excitation light; and a plurality of first band-pass filters configured to transmit beams of the excitation light with different wavelength bands, 
 the light detector comprises: a first photodetector configured to, from among beams of the emitted light, detect emitted light with a wavelength longer than the second separation wavelength; and a second photodetector configured to, from among beams of the emitted light, detect emitted light with a wavelength shorter than the second separation wavelength, and 
 the controller switches one of the first band-pass filters, one of the second band-pass filters, one of the first wavelength separation elements, and one of the second wavelength separation elements in an integral manner, according to a determined wavelength of the excitation light. 
 
     
     
       9. An inspection method for inspecting an object comprising a substrate bearing a plurality of light-emitting elements, the method comprising the steps of:
 inputting information on an emission color of a light-emitting element; 
 deriving an absorption edge wavelength of the substrate of the object and a peak wavelength of an emission spectrum of the light-emitting elements, based on the information on the emission color; and 
 controlling the light source in such a way as to make a wavelength of excitation light longer than the absorption edge wavelength and shorter than the peak wavelength, the excitation light being emitted from the light source onto the light-emitting element.